Compositions stabilized with benzoyloxybenzamides

ABSTRACT

Benzoyloxybenzamides having the formula ##SPC1## 
     Wherein 
     R 1  and R 2  are lower alkyl or cycloalkyl, 
     R 3  and R 4  are hydrogen, lower alkyl or cycloalkyl, 
     R 5  is hydrogen or alkyl, 
     R 6  is alkyl when n is 1 and alkylene when n is 2 or greater 
     Are useful as stabilizers of organic materials such as polyolefins.

This application is a divisional application of U.S. application Ser.No. 318,325, filed on Dec. 26, 1972, now U.S. Pat. No. 3,880,910.

BACKGROUND OF THE INVENTION

Polymeric materials have one important deficiency which must be overcomebefore they can be used in various commercial applications. Thisdeficiency is the susceptibility to oxidative and actinic degradation.Many varieties of compounds have been known to be useful as stabilizersof various polymers, but all of them have certain deficiencies whichlimits the usefulness of such stabilizers. Thus, one class ofstabilizers disclosed in the prior art that is related to the compoundsof this invention is hindered hydroxybenzoates disclosed in U.S. Pat.Nos. 3,029,276; 3,112,338; 3,206,431 and 3,502,613.

Most of the compounds disclosed in said patents are various esters of3,5-dialkyl-4-hydroxybenzoic acids while this invention deals with4-(3,5-dialkyl-4-hydroxybenzoyloxy)-mono or dialkylbenzamides. Otherdifferences are that the phenyl ring in the benzoate ring is completelyunsubstituted while the corresponding group in the compounds of thisinvention has at least one alkyl substituent.

The compounds of this invention have many advantages over the prior artcompounds. The instant compounds have improved thermal stability. Thisfeature is important because the polymer substrates are subjected tohigh temperature processing during manufacturing stages. Furthermore,the compounds of this invention have better gas fading properties andhave better aqueous and organic solvent extraction resistance than theprior art compounds.

DETAILED DISCLOSURE

This invention relates to hindered benzoyloxybenzamide compounds andorganic compositions stabilized therewith. More specifically, thesecompounds are useful as stabilizers of organic materials which aresubject to thermal, oxidative and ultraviolet light degradation. Thenovel benzoyloxybenzamide compounds can be represented by the formula##SPC2##

Wherein

R¹ and R² are (lower)alkyl or (lower) cycloalkyl groups,

R³, R⁴ and R⁵ are independently hydrogen, (lower)alkyl or(lower)cycloalkyl,

R⁶ is an alkyl group having up to 24 carbon atoms when n is 1 andalkylene group having up to 10 carbon atoms when n is 2 to 6, and

N IS AN INTEGER 1 TO 6 AND PREFERABLY 1 OR 2.

Each of the groups R¹, R² and R³ can be the same or different(lower)alkyl groups having from 1 to 8 carbon atoms, namely, n-propyl,isopropyl, n-butyl, sec-butyl, tert-butyl, sec-amyl, tert-amyl, n-hexyl,sec-hexyl, sec-octyl, tert-octyl and the like. These groups can also be(lower)cycloalkyl groups having 4 to 8 carbon atoms, such as cyclobutyl,cyclopentyl, cyclohexyl or cyclooctyl groups. The group R⁴ can behydrogen or any of the alkyl or cycloalkyl group discussed above.

Although groups R¹, R², R³ and R⁴ can be any (lower)alkyl groups statedabove, it is preferable that R¹ and R² groups be secondary or tertiaryalkyl groups having from 4 to 8 carbon atoms and most preferablytertiary alkyl. Tertiary-butyl group is found to be very effective. Theabove formula indicates that R³ and R⁴ can be substituted on any of thefour open positions in the benzene ring but preferably both groups areortho to the benzoic acid moiety. The formula also indicates that thegroup ##STR1## can be bonded to the phenyl ring in either meta or paraposition in relation to the hindered hydroxybenzoic acid moiety.

The group R⁵ can be hydrogen, (lower)alkyl or (lower)cycloalkyldiscussed above. The group R⁶ can be either an alkyl group of up to 24carbon atoms or an alkylene group of up to 10 carbon atoms. Illustrativeexamples of alkyl groups are methyl, ethyl, butyl, hexyl, octyl,dodecyl, hexadecyl, octadecyl, eicosyl, tetracosyl and the like.Illustrative examples of alkylene groups are methylene, ethylene,propylene, butylene, hexylene, octene, decene and the like. Alkylenegroup of 1 to 6 carbon atoms is preferred at this time from economicalstandpoint.

Following are illustrative examples of the compounds of this invention:

N-n-octadecyl-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzamide

N-methyl-N-n-octadecyl-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzamide

N,N-di-n-octyl-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzamide

N,N-diethyl-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylthiobenzamide

N-`(1,1,3,3-tetramethylbutyl)-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzamide`

N-ethyl-N-p-tolyl-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzamide

N-tetracosyl-4-(3,5-dimethyl-4-hydroxybenzoyloxy)-3,5-dimethylbenzamide

N,N-dicyclooctyl-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3-t-butylbenzamide

N-n-octyl-4-(3,5-di-isopropyl-4-hydroxybenzoyloxy)-3,5-di-isopropylbenzamide

N,N'-hexamethylene-bis-`4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzamide`

N,N'-1,2-ethylene-bis-`4-(3,5-di-tert.butyl-4-hydroxybenzoyloxy)-5-t-butylbenzamide`

The compounds of this invention when R¹ and R² are different from R³ andR⁴ can be prepared by reacting a hindered phenolic acid chloride such as3,5-di-tert-butyl-4-hydroxybenzoyl chloride with an appropriatesubstituted hydroxybenzamide at a temperature of from about 50° to200°C. Compounds where R¹ and R² are the same as R³ and R⁴ can beprepared by reacting two moles of a dialkyl substituted hydroxybenzoylhalide with one mole of a base to yield an intermediate compound whichis (di-alkyl substituted hydroxybenzoyloxy)-dialkyl benzoyl halide whichin turn is reacted with a primary or a secondary amine to give thedesired product. The basic materials which can be employed are trialkylamines such as triethyl amine, tripropyl amine, triisopropyl amine,tributyl amine, triamyl amine, sodium or potassium hydroxide, sodium orpotassium carbonates or other similar proton acceptors. Both reactionsmentioned above can be carried out neat in some cases or in anon-reactive solvent such as a hydrocarbon as for example, hexane,cyclohexane, heptane, non-reactive chlorinated hydrocarbon, mineral oil,and preferably benzene or toluene.

The preparation of these compounds is further illustrated in greaterdetail in the examples below.

EXAMPLE 1 Preparation of4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzoyl chloride

To 445 ml. of a toluene solution containing 107.2 grams of3,5-di-t-butyl-4-hydroxybenzoyl chloride (0.40 moles) cooled to 10°C wasadded 24.4 grams (0.24 moles) of triethylamine over a period 20 minutesat 10° to 15°C. The turbid reaction mixture was maintained at roomtemperature for about 19 hours and then heated at 80°C for 1 hour. Theprecipitate was removed by filtration and washed with a little toluene.The clear filtrate was concentrated in vacuo at 40° to 50°C at 20 mm.Hg. pressure and kept at this same temperature for 45 minutes at 20 mm.Hg. pressure to yield 105 grams of residue. The residue was trituratedwith 200 ml. of warm petroleum ether, and the slurry cooled. The whitecrystals were filtered yielding 70 grams of the product. Afterrecrystallization from heptane and acetonitrile and drying at 95°C for 5hours at 0.1 mm Hg. pressure the melting point of the product was210°-213°C.

EXAMPLE 2 Preparation ofN-n-octadecyl-4-(3,5-di-tert.butyl-4-hydroxybenzoyloxy)-3,5-di-tert.butylbenzamide

10.10 grams of4-(3,5-di-tert.butyl-4-hydroxybenzoyloxy)-3,5-di-tert-butylbenzoylchloride 5.4 grams of n-octadecylamine and 2.0 grams of triethylaminewere heated together in about 100 ml of toluene for about 5 hours at 90°to 98°C. The precipitated triethylamine hydrochloride was filtered. Thefiltrate was washed with water and dried over anhydrous sodium sulfate.The dried toluene solution was concentrated to remove toluene underreduced pressure yielding 14.5 grams of the product. The product wascrystallized twice from acetonitrile and melted at 139° to 140°C.

EXAMPLE 3 Preparation ofN-methyl-N-n-octadecyl-4-(3,5-di-tert.butyl-4-hydroxybenzoyloxy)-3,5-di-tert.butylbenzamide

This compound was made according to the procedure of Example 2, and wasisolated as an oil (14.5 grams).

EXAMPLE 4 Preparation ofN,N-di-n-octyl-4-(3,5-di-tert-butyl-4-hydroxybenzoyloxy)-3,5-di-tert-butylbenzamide

To 4.83 grams of di-n-octylamine and 2.0 grams of triethylaminedissolved in 40 ml of toluene was added dropwise at 35° to 40° over aperiod of 10 minutes 10.0 grams of4-(3,5-di-tert-butyl-4-hydroxybenzoyloxy)-3,5-di-tert-butyl-benzoylchloride dissolved in 30 ml of toluene. The reaction mixture was stirredat 85° to 90°C for 2 hours. After cooling to room temperature, thereaction mixture was filtered to remove the precipitated triethylaminehydrochloride. The filtrate was washed with water and dried overanhydrous sodium sulfate. After removal of the toluene by distillation,the product was isolated as white crystals (m.p. 145°-146°) bysuccessive crystallization from acetonitrile and isopropanol.

EXAMPLE 5 Preparation ofN,N-diethyl-4-(3,5-di-tert-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzamide

The compound of this example was made substantially according to theprocedure of example 4 and after successive crystallization frommethanol and isopropanol yielded the desired product as white crystalsmelting at 203°-205°C.

EXAMPLE 6

Following the procedure of Example 4, dimethylamine andN,N'-di-n-butylamine are reacted respectively with4-(3,5-dimethyl-4-hydroxybenzoyloxy)-3,5-dimethylbenzoyl chloride and4-(3,5-diisopropyl-4-hydroxybenzoyloxy)-3,5-diisopropylbenzoyl chlorideto yieldN,N'-dimethyl-4-(3,5-dimethyl-4-hydroxybenzoyloxy)-3,5-dimethylbenzamideandN,N'-di-n-butyl-4-(3,5-diisopropyl-4-hydroxybenzoyloxy)-3,5-diisopropylbenzamide.

EXAMPLE 7 Preparation ofN-(1,1,3,3-tetramethylbutyl)-4(3,5-di-tert-butyl-4-hydroxybenzoyloxy)-3,5-di-tert-butylbenzamide

To 143 ml. of a 0.7 molar solution of 3,5-di-tert-butyl-4-hydroxybenzoylchloride in toluene 5.05 grams of triethylamine was added dropwise at10° to 15°C over a period of 10 minutes and the reaction mixture stirredat room temperature for 2 hours. An additional 5.05 grams oftriethylamine was added followed by the dropwise addition of 6.48 gramsof tert-octylamine dissolved in 10 ml. of toluene at 20° to 30°C. Thereactants were stirred at room temperature for 20 hours. The precipitatetriethylamine hydrochloride was filtered and washed with a littletoluene the washings being added to the filtrate containing the product.The filtrate was washed successively with water, 2N aqueous hydrochloricacid and again with water, the organic phase being dried over anhydroussodium sulfate. The toluene solution was concentrated in vacuo to yieldthe product as a glassy residue. The residue was crystallizedsuccessively from heptane and acetonitrile to yield the product as whitecrystals melting at 213°-215° C.

EXAMPLE 8 Preparation ofN-ethyl-N-p-tolyl-4-(3,5-di-tert-butyl-4-hydroxybenzoyloxy)-3,5-di-tert-butylbenzamide

By substituting N-ethyl-p-toluidine in Example 7 and following basicallythe above procedure, the subject compound is isolated as white crystals(m.p. 214°-216°C) after crystallization successively from acetonitrileand toluene.

EXAMPLE 9

Following the procedure of Example 8, n-octylamine is reacted with4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-5-t-butylbenzoyl chloride toyieldN-n-octyl-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-5-t-butylbenzamide.

The benzoyloxybenzamides of this invention are stabilizers of organicmaterial normally subject to thermal, oxidative or actinic lightdeterioration. Materials which are thus stabilized include syntheticorganic polymeric substances such as vinyl resins formed from thepolymerization of vinyl halides or from the copolymerization of vinylhalides with unsaturated polymerizable compounds, e.g., vinyl esters,α,β-unsaturated ketones, α,β-unsaturated aldehydes and unsaturatedhydrocarbons such as butadienes and styrene; poly-α-olefins such aspolyethylene, polypropylene, polybutylene including copolymers ofα-olefins; dienes such as polybutadiene, polyisoprene, and the like,including copolymers with other monomers; polyurethanes and polyamidessuch as polyhexamethylene adipamide and polycaprolactam; polyesters suchas polyethylene terephthalates; polycarbonates; polyacetals such aspolyethylene terephthalate polyacetal; polystyrene; polyethyleneoxide;and copolymers such as those of high impact polystyrene containingcopolymers of butadiene and styrene and those formed by thecopolymerization of acrylonitrile, butadiene and/or styrene.

Other materials which can be stabilized by the compounds of the presentinvention include lubricating oil of the aliphatic ester type, i.e.,di(1,2-ethylene)-azelate, pentaerythritol tetracaproate, and the like;animal and vegetable derived oils, e.g., linseed oil, fat, tallow, lard,peanut oil, cod liver oil, castor oil, palm oil, corn oil, cottonseedoil, and the like; hydrocarbon materials such as gasoline, mineral oil,fuel oil, drying oil, cutting fluids, waxes, resins, and the like, saltsof fatty acids such as soaps and the like; and alkylene glycols, e.g.,β-methoxyethyleneglycol, methoxytriethyleneglycol, triethylene glycol,octaethyleneglycol, dibutyleneglycol, dipropyleneglycol and the like.

Of particular importance are polyolefins and especially polypropylenebecause these benzoyloxybenzoates are particularly effective as UVstabilizers in polypropylene.

In general, the stabilizers of this invention are employed from about0.01 to about 5% by weight of the stabilized composition, although thiswill vary with the particular substrate and application. An advantageousrange is from about 0.05 to about 2% and especially 0.1 to about 1%.

For addition to polymeric substrates, the stabilizers can be blendedbefore polymerization or after polymerization, during the usualprocessing operations, for example, by hot-milling, the composition thenbeing extruded, pressed, or the like into films, fibers, filaments,hollow spheres and the like. The heat stabilizing properties of thesecompounds advantageously stabilize the polymer against degradationduring such processing at the high temperature generally encountered.The stabilizers can also be dissolved in suitable solvents and sprayedon the surface of films, fabrics, filaments or the like to provideeffective stabilization.

These compounds can also be used in combination with other additivessuch as antioxidants, sulfur-containing esters such asdistearyl-β-thiodipropionate (DSTDP), dilauryl-β-thiodipropionate(DLTDP) in an amount of from 0.01 to 2% by weight of the organicmaterial, and the like, pourpoint depressants, corrosion and rustinhibitors, dispersing agents, demulsifiers, antifoaming agents, carbonblack, accelerators and other chemicals used in rubber compounding,plasticizers, color stabilizers, di- and tri-alkyl- and-alkylphenylphosphites, heat stabilizers, ultraviolet light stabilizers,antiozonants, dyes, pigments, metal chelating agents, dyesites and thelike. Often combinations such as these, particularly the sulfurcontaining esters, the phosphites and/or the ultraviolet lightstabilizers will produce superior results in certain applications tothose expected by the properties of the individual components.

The following formula represents co-stabilizers which are in certaininstances very useful in combination with the stabilizers of thisinvention: ##STR2## wherein R is an alkyl group having from 6 to 24carbon atoms; and n is an integer from 1 to 6. Especially usefulcompounds of this type are dilauryl-β-thiodipropionate anddistearyl-β-thiodipropionate. The above co-stabilizers are used in theamount of from 0.01 to 2% by weight of the organic material, andpreferably from 0.1 to 1%.

Although the compounds of this invention are also effective as thermalstabilizers, if the processing of the polymer is carried out at hightemperatures it is advantageous to incorporate additional anti-oxidants.

The antioxidant compounds that can be employed are various hinderedphenolic compounds which can be illustrated by the compounds listedbelow:

di-n-octadecyl(3-t-butyl-4-hydroxy-5-methylbenzyl)malonate

2,6-di-t-butylphenol

2,2'-methylene-bis(6-t-butyl-4-methylphenol)

2,6-di-t-butylhydroquinone

octadecyl-(3,5-di-t-butyl-4-hydroxybenzylthio)acetate

1,1,3-tris(3-t-butyl-6-methyl-4-hydroxyphenyl)butane

1,4-bis(3,5-di-t-butyl-4-hydroxybenzyl)-2,3,5,6-tetramethylbenzene

2,4-bis-(3,5-di-t-butyl-4-hydroxyphenoxy)-6-(n-octylthio)-1,3,5-triazine

2,4-bis-(4-hydroxy-3,5-di-t-butylphenoxy)-6-(n-octylthioethylthio)-1,3,5-triazine

2,4-bis-(n-octylthio)-6-(3,5-di-t-butyl-4-hydroxyanilino)-1,3,5-triazine

2,4,6-tris-(4-hydroxy-3,5-di-t-butylphenoxy)-1,3,5-triazine

n-octadecyl-β-(3,5-di-t-butyl-4-hydroxyphenyl)propionate

n-octadecyl-3,5-di-t-butyl-4-hydroxybenzoate

2-(n-octylthio)ethyl-3,5-di-t-butyl-4-hydroxybenzoate

stearamido N,N-bis-`ethylene3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate`

1,2-propylene glycol bis-`3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate`

pentaerythritol tetrakis-`3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate`

dioctadecyl-3,5-di-t-butyl-4-hydroxybenzyl-phosphonate

di-n-octadecyl-1-(3,5-di-t-butyl-4-hydroxyphenyl)-ethanephosphonate

The above antioxidants have been listed only for the purpose ofillustration and it is important to note that any other antioxidant canbe employed with the same improved results. The above exemplifiedantioxidants are disclosed in greater detail in the following patents:Netherlands Pat. No. 67/1119, issued Feb. 19, 1968; Netherlands Pat. No.68/03498 issued Sept. 18, 1968; U.S. Pat. Nos. 3,255,191; 3,330,859;3,281,505; 3,285,855; 3,364,250; 3,368,997 and 3,357,944.

To further illustrate the present invention additional examples arepresented without introducing any limitations to the description of theinvention.

OUTDOOR LIGHT EXPOSURE TEST 15 Denier Oriented Monofilaments

The additives are solvent blended (e.g., methylene chloride) withpowdered polypropylene (Hercules Profax 6501). The solvent is thenremoved at room temperature in a vacuum oven with a slight air bleed.The dry mixture is melt-extruded at 450°F and pelletized. The pelletsare reextruded through a monofilament die, melt spun and hot oriented4:1 by means of a set of cold and hot Godet rolls to give 15 denier(nominal) monofilaments.

The test results reported in Examples of Table I show the percentage ofretention of the original tenacity by a fiber after having been exposedto the indicated number of Kilolangleys (Kly) of Florida exposure. ALangley is a measure of energy accumulated by the fiber.

Table I shows the results of the above described outdoor test indicatingamounts of the additives present. Thus, in the Additives column is giventhe percentage of the compound prepared in the indicated Example whichis present in the polypropylene composition in addition to the additivespresent in the base formulation. The remaining two columns show thenumber of Kilolangleys of exposure in Florida at the indicatedpercentage of retention of the original tenacity to which the fibershave been subjected.

                  TABLE I                                                         ______________________________________                                        Outdoor Exposure of 15 Denier                                                 Polypropylene Monofilaments in Florida                                        ______________________________________                                        Base Formulation:                                                                            0.2% IRGANOX 1093                                                             0.1% Calcium Stearate                                                             Kilolangleys to                                                                     30%       50%                                        Ex.                      Retention Retention                                  No.    Additive          of Tenacity                                                                             of Tenacity                                ______________________________________                                        10   Base Formulation    41        36                                         11   0.5% N-methyl-N-n-octadecyl-                                                   4-(3,5-di-tert-butyl-4-                                                       hydroxybenzoyloxy)-3,5-di-                                                    tert-butylbenzamide                                                                              91        80                                         ______________________________________                                         *IRGANOX 1093 is an antioxidant dioctadecyl                                   3,5-di-t-butyl-4-hydroxybenzylphosphonate                                

proportionately good stabilization is obtained when in the compositionsof Table I the compounds of this invention are present in theconcentrations of 0.1% to 1%.

ARTIFICIAL LIGHT EXPOSURE TEST

Deterioration of most polymers caused by ultraviolet light is so slow atambient temperatures even in the absence of stabilizers, that testing ofthe effects of stabilizers generally must be conducted either at highertemperatures or in an accelerated artificial light exposure device inorder to yield results in a convenient period of time. The testconducted on polymers using an artificial light exposure device isdescribed below:

a. Sample Preparation

5 mil Film -- Unstabilized polypropylene Powder (Hercules Profax 6501)is thoroughly blended with the indicated amounts of additives. Theblended material is then milled on a two roll mill for 5 minutes at182°C. The milled sheet is then compression molded at 220°C into 5 milthick film under a pressure of 175 psi and water cooled in the press.

b. Testing Method

This test is conducted in a FS/BL unit, basically of the AmericanCyanamid design, which consists of 40 tubes of alternating fluorescentsun lamps and black lights (20 of each). The 5 mil sample film aremounted on 3 × 1 inch IR card holders with 1/4 inch × 1 inch windows andare placed on a rotating drum 2 inches from the bulbs in the FS/BL unit.The time in hours is noted for the development of 0.5 carbonylabsorbance units as determined on an Infrared Spectophotometer. Thedevelopment of carbonyl functional groups in the polymer is proportionalto the amount of degradation caused by the ultraviolet light exposure.

The test results reported below were obtained according to theprocedures described above. The amounts of the additives are expressedin weight percent based on the weight of the polymer

                  TABLE II                                                        ______________________________________                                        Artificial Light Exposure of 5 mil Film                                       ______________________________________                                                                    Time in Hours                                     Ex.                         to .5 Carbonyl                                    No.    Formulation*         Absorbance Units                                  ______________________________________                                        12   0.5% N-n-octadecyl-4-(3,5-di-tert.-                                            butyl-4-hydroxybenzoyloxy)-3,5-                                               di-tert.butylbenzamide                                                                              170                                               13   0.25% N-n-octadecyl-4-(3,5-di-tert.-                                           butyl-4-hydroxybenzoyloxy)-3,5-                                               di-tert.butylbenzamide                                                       0.25% TINUVIN 327**    510                                               14   0.5% N-methyl-N-n-octadecyl-4-(3,5-                                            di-tert.butyl-4-hydroxybenzoyloxy)-                                           3,5-di-tert-butylbenzamide                                                                          310                                               15   0.25% N-methyl-N-n-octadecyl-4-(3,5-                                           di-tert.butyl-4-hydroxybenzoyloxy)-                                           3,5-di-tert-butylbenzamide                                                   0.25% TINUVIN 327      740                                               16   0.5% N,N-diethyl-4-(3,5-di-tert-butyl-                                         4-hydroxybenzoyloxy)-3,5-di-t-butyl-                                          benzamide             800                                               17   0.25% N,N-diethyl-4-(3,5-di-tert-butyl-                                        4-hydroxybenzoyloxy)-3,5-di-t-butyl-                                          benzamide                                                                    0.25% TINUVIN 327      1370                                              18   0.5% N,N-di-n-octyl-4-(3,5-di-tert-butyl-                                      4-hydroxybenzoyloxy)-3,5-di-tert-                                             butyl-benzamide       740                                               19   0.025% N,N-di-n-octyl-4-(3,5-di-tert-butyl-                                    4-hydroxybenzoyloxy)-3,5-di-tert-                                             butyl-benzamide                                                              0.25% TINUVIN 327      1310                                              20   ControlAbout           120                                               ______________________________________                                         *Each of the samples tested and the control contains 0.2% of                  di-n-octadecyl(3,5-di-t-butyl-4-hydroxybenzyl)phosphonate which is an         antioxidant which prevents oxidative degradation of polypropylene.            **TINUVIN 327 is UV absorber                                                  2(2'-hydroxy-3',5'-di-t-butyl-phenyl)-5-chlorobenzotriazole.             

The compositions of Table II are equally stabilized when TINUVIN 327 isreplaced with the following compounds:

a. 2-hydroxy-4-methoxy-5-sulfobenzophenone trihydrate

b. 2-hydroxy-4-n-octoxybenzophenone

c. `2,2'-thiobis(4-t-octylphenolate)`-n-butylamine nickel II

d. p-octylphenyl salicylate

e. 2,2'-dihydroxy-4,4'-dimethoxybenzophenone

f. 2(2'-hydroxy-5'-methylphenyl)-benzotriazole

EXAMPLE 29

Pellets (500 g) of unstabilized nylon-6,6 (Zytel 101, DuPont) are placedin a Kitchen Aid Mixer. With mixing a solution of 0.5% (based on theweight of nylon) ofN-n-octadecyl-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzamidein 20 ml of methylene chloride is added slowly. Sodium hypophosphite(0.5 gm. 0.1%) is dissolved in 20 ml of water and added slowly withmixing to the nylon pellets after the antioxidant solution has beenadded and most of the methylene chloride has evaporated. The stabilizedpellets are dried at 80°C at <<1mm Hg. for 4 hours.

The polyamide formulation is extruded at 600°F through at 1/4 inch dieinto a rod which is water cooled and chopped into pellets. A 3/4 inchBrabender extruder, equipped with a nylon screw, is used. The pelletsare dried at 80°C at <1mm for 4 hours.

The dried pellets are reextruded into 5 mil (nominal) monofilament fiberwhich is subsequently oriented (4:1). The oriented fibers are exposed tooutdoor weathering (direct and under glass) and tensile measurement ismade periodically. The sample is considered to have failed when it loses50% of its original tenacity. The sample stabilized with the above notedbenzoate retained tensile strength for a much longer period than theunstabilized sample.

EXAMPLE 30

Unstabilized high impact polystyrene resin is dry blended with 0.01% byweight of the resin ofN-methyl-N-n-octadecyl-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzamide.The resin is then extrusion compounded on a 1 inch 24/1=L/D extruder,melt temperature 500°F and pressed for 7 minutes at a temperature of163°C and a pressure of 2000 psi into a sheet of uniform thickness of100 mil. The sheets are then cut into plaques of 2 inch × 2 inch. Theplaques are then exposed in a FS/BL exposure device and colormeasurements made periodically using a Hunter Color Difference MeterModel D25. The polystyrene samples stabilized with the above benzoatedeveloped the undesirable yellow discoloration substantially later aftersuch discoloration occured in the unstabilized samples.

EXAMPLE 31

Unstabilized linear polyethylene is solvent blended in methylenechloride with 0.5% by weight of the substrate ofN,N-di-n-octyl-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzamideand then vacuum dried. The resin is then extruded at 450°F as describedin Example 30. Thereafter, the test procedure of Example 30 is followedand the light stability of the samples determined. Polyethylenestabilized with the above benzoate is found to be much more stable thanthe unstabilized polyethylene or the polyethylene stabilized only withan antioxidant.

EXAMPLE 32

A quantity of SBR emulsion containing 100 g of rubber (500 ml of 20% SBRobtained from Texas U.S., Synpol 1500) previously stored under nitrogen,is placed in a beaker and stirred vigorously. The pH of the emulsion isadjusted to 10.5 with a 0.5N NaOH solution.

To the emulsion is added 50 ml of 25% NaCl solution. A 6% NaCl solutionadjusted with hydrochloric acid to a pH 1.5 is added in a thin streamwith vigorous stirring. When pH 6.5 is reached, the rubber begins tocoagulate and the addition is slowed down in order to maintain uniformagitation. The addition of the acidic 6% NaCl solution is terminatedwhen a pH 3.5 is reached. The coagulated crumb-rubber slurry at pH 3.5is stirred for 1/2 hour.

The coagulated rubber is isolated by filtration through cheese cloth,and rinsed with distilled water. After three subsequent washings withfresh distilled water, the coagulated rubber is dried, first at 25 mm Hgand finally to constant weight under high vacuum (<1 mm) at 40°-45°C.

The dried rubber (25 g) is heated under nitrogen at 125°C in a Brabendermixer and to this is added with mixing 0.25 g (0.5%) ofN,N-diethyl-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzamide.The composition is mixed for 5 minutes after which it is cooled andcompression molded at 125°C into 5 inches × 0.025 inch plaques.

The plaques are exposed to a xenon arc weatherometer and the colormeasurement (L-b) is made after 45, 125 and 290 hours. The samplesstabilized with the above benzoate is found to be much more light stablethan the unstabilized samples.

EXAMPLE 33

To 50 g of polyacetal resin containing 0.1% of an acid scavenger,dicyandiamide, is added 0.2% by weight ofN-ethyl-N-p-tolyl-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzamide,and milled for 7 minutes at 200°C in a Brabender Plastirecorder. Themilled formulation is subsequently pressed into a 40 mil sheet at 215°Cat 350 psi for 90 seconds then cooled quickly in a cold press at 350psi. The stabilized sheets are then remolded for 2 minutes at contactpressure and for 3 minutes at 300 psi at 215°C to give plaques 11/2 inch× 21/4 inch × 125 mil. Thereafter, the testing procedure of Example 30is followed to determine the light stability of the samples. Thestabilized samples are found to be much more stable than theunstabilized samples.

EXAMPLE 34

Unstabilized thoroughly dried polyethylene terephthalate chips are dryblended with 1.0% ofN-n-octyl-4-(3,5-di-t-butyl-4-hydroxybenzoyloxy)-5-t-butyl benzamide.60/10 denier multifilament is melt spun at a melt temperature of 290°C.The oriented fiber is wound on white cards and exposed in a Xenon ArcFadeometer. Color measurements are made periodically with a Hunter ColorDifference Meter Model D25. The stabilized samples are found to be muchmore light stable than the unstabilized samples.

EXAMPLE 35 Preparation ofN,N'-hexamethylene-bis-`(3,5-di-tert.butyl-4-hydroxybenzoyloxy)-3,5-di-tert.-butylbenzamide`

15.7 grams of 1,6-hexanediamine dissolved in 200 ml. of toluene wasadded dropwise to a solution of 14.6 grams of3,5-di-tert.butyl-4-hydroxybenzoyloxy)-3,5-di-tert.butylbenzoyl chlorideand 2.83 grams of triethylamine in 300 ml. of toluene at such a rate sothat the temperature was kept below 35°C. The reaction mixture washeated at reflux (110° to 112°C) for about 4 hours. The reaction mixturewas diluted with 600 ml. of chloroform and successively washed withwater, saturated sodium carbonate and water. The toluene solution wasdried over sodium sulfate, yielding the desired product after removal ofthe toluene by vacuum distillation.

What is claimed is:
 1. A composition of matter stabilized againstdegradation which comprises an organic material subject to oxidative andultraviolet light degradation containing from about 0.01 to about 5.% byweight of a stabilizing compound of the formula ##SPC3##wherein R¹ andR² are (lower)alkyl or (lower)cycloalkyl groups, R³, r⁴ and R⁵ areindependently hydrogen, (lower)alkyl or (lower)cycloalkyl, R⁶ is analkyl group having up to 24 carbon atoms when n is 1 and an alkylenegroup having up to 10 carbon atoms when n is 2 to 6, and n is an integerfrom 1 to
 6. 2. The composition of claim 1 wherein R¹ and R² arebranched alkyl,R⁶ is alkylene and n is
 2. 3. The composition of claim 2wherein R³ and R⁴ are alkyl groups.
 4. The composition of claim 2wherein R⁶ is alkyl and n is
 1. 5. The composition of claim 1 whereinR¹, R², R³ and R⁴ are tert-butyl groups, R⁶ is alkyl and n is
 1. 6. Thecomposition of claim 1 wherein the stabilizing compound isN-n-octadecyl-4-(3,5-di-tert.butyl-4-hydroxybenzoyloxy)-3,5-di-tert.butylbenzamide.7. The composition of claim 1 wherein the stabilizing compound isN-methyl-N-n-octadecyl-4-(3,5-di-tert.butyl-4-hydroxybenzoyloxy)-3,5-di-tert-butylbenzamide.8. The composition of claim 1 wherein the stabilizing compound isN,N-di-n-octyl-4-(3,5-di-tert-butyl-4-hydroxybenzoyloxy)-3,5-di-tert-butylbenzamide.9. The composition of claim 1 wherein the stabilizing compound isN,N-diethyl-4-(3,5-di-tert-butyl-4-hydroxybenzoyloxy)-3,5-di-t-butylbenzamide.10. The composition of claim 1 wherein the stabilizing compound isN-(1,1,3,3-tetramethylbutyl)-4-(3,5di-tert-butyl-4-hydroxybenzoyloxy)-3,5-di-tert-butylbenzamide.11. The composition of claim 1 wherein the stabilizing compound isN-ethyl-N-p-tolyl-4-(3,5-di-tert-butyl-4-hydroxybenzoyloxy)-3,5-di-tert-butylbenzamide.12. The composition of claim 1 wherein the organic material is apolyolefin.
 13. The composition of claim 1 wherein the organic materialis polypropylene.
 14. The composition of claim 13 which contains aphenolic antioxidant.
 15. The composition of claim 13 which contains aphenolic antioxidant and a UV absorber.